土质边坡锚杆受力特性模型试验研究

Model test of mechanical characteristics of anchor bolts in soil slope

针对滇黔地区的风化玄武岩土质边坡情况,进行边坡锚杆室内模型试验。分别对单根锚杆的应变分布曲线,同列锚杆在坡面、滑面及锚固段末端处的应变曲线,以及坡面渗水前后、不同加载量级的锚杆应变分布曲线,固定拉拔力下不同锚固长度锚杆的荷载位移情况进行了分析。结果表明,锚杆应变沿杆长呈中间大、两端小的曲线分布,而锚杆变形较多集中在坡顶以下的第一排,且坡脚和坡顶的应变比其他部位要大,更容易被破坏。加荷初期锚杆应变出现负值,表明锚杆是以拉应力为主的拉压弯复合构件。

Model tests for slope anchor bolts were carried out aiming at the conditions of weathered basalt soil slope in western Guizhou Province. The tests were to explore the strain distribution curves under various conditions such as the curves of a single bolt, the curves of bolts in a row at slope surface, slide plane and bolt ends, and curves before and after slope seepage or under different load levels. We studied the load - displacement curves of bolts with various anchorage lengths that were under the same drawing force. The results show that the strain distribution along a bolt is a curve characterized as larger in middle and smaller at two ends, while the deformations of bolts generally concentrate at the first row under slope top and the strain at toe and top of a slope is relatively larger than other parts, which results in easier destruction. At the beginning stage of a load process, the nega- tive strain of the anchor bolts manifests that the anchor bolts is a tension - compression - bending composite number.